Improvement in harvesters



UNITED STATES K. H. O. PRESTON, OE MANLIUS, NEW YORK, ASSIGNOR TO E. P. RUSSELL,

PATENT OFFICE.

OF SAME PLACE.

IMPROVEMENT IN HARVESTERS.

Specication forming part of Letters Patent No. 33,975, dated December 17, 1861.

To @ZZ whom t may concern: n Beit known that I, KING H. C. PRESTON, of Manlius, in the county of Onondaga and State of New York7 have invented a new and useful Improvement in Harvesters, and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawing, which forms a part of this specification.

My improvement in harvesters consists in transmitting the requisite rate and force of motion from the driving-wheel A to the crankshaft C through the medium of the series of rollers e c which are pivoted to the face of the said driving-wheel, and the tapering` single screw-thread d, which projects from the periphery of the said crank-shaft.

By employing but a single screw-thread upon the crank-shaft O for the aforesaid series of rollers e e to act upon, and by giving the said screw-thread agradually-tapering shape, I am enabled to place the crank-shaft in such a p0- sition that its axis will be exactly oppositeto a portion of an imaginary circular line passing through the centers of the pivots of each of the rollers e e, and I am also enabled to place the saidrollers in such near proximity to each other that an unusually-smooth movement is imparted to the crank-shaft, and everything like backlash 7 in the working of the said screw-thread d and the rollers e e isentirely prevented. If the screw-thread l were of uniform thickness -from I,end to end, the rollers e c would have to be placed at a'much greater `distance from each other, and consequently a greatamount of backlash would be the result. s f

The position of the crank-shaft with relation to the pivots ofthe series of rollers e c, before referred to, enables me to act upon the thread d of the crank-shaft by means of rollers, instead of oval-headed pins, as is the case in the Haviland harvester,77 and the said position of the crankshaft in my machine also enables me to use rollers e e which have tapering bearing-peripheries of substantially the shape represented in the drawings.

The tapering screw-thread (l I shall generally cast in one piece with a tube, B, and then tit the said tube to the crankshaft in. such a manner that it'will only carry the said shaft around with it when it is rotated by means ol' the forward movement of the driving-wheel A. rlhe taperingshape of the screw-thread el enables the pattern of the thread-bearing tube B to be easily drawn from the sand during the process of molding J[he same preparatory to casting.

- lVhat I claim as my invention, and desire to secure by Letters Patent, is-

l. The tapering shape of the single screwthread d, which I employ for the purpose of enabling the desired amount of motion to be communicated to the crankshaft G, substantially as herein set forth.

2. Vhen a tapering single screw-thread is combined with a shaft, Veither directly or through the medium of a tube or collar, Ialso claim acting upon said screw-thread by means of a series of pivoted rollers and a drivingwheel for carrying the same, substantially as set forth.

3. Vhen a tapering single screw-thread is combined with a shaft, either directly or through the medium of a tube or collar, I also claim acting upon the said screwthread through the medium of a series of tapering pivoted rollers and a suitable driving-wheel, substantially in the manner herein set forth.

'Ihe above specification of my improvement in harvesters signed by me this 7th day of September, 1861.

K. H. C. PRESTON.

W'itnesses:

Z. C. RoEnlNs, RANDQLPH CoYLE, Jr. 

